I was searching through YouTube for reviews M&P with red dots last week and ran across a couple that claimed the 2.0 slide is thinner which makes it very difficult to cut for a red dot base. Maybe the factory has problems doing the same.

The source for this was a couple of random guys on YouTube, take it FWIW.

A local gunsmith milled my M&P 2.0 with a 4.25 inch barrel about 8 months ago and it's worked perfectly since. I was interested in a 5 inch barrel and was wanting to get the pro core but didn't want to if there was an update coming up.